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Standard NPT Tap Drill Sizes Chart

March 13th, 2013

posted by AutoDrill

StandardNPTTapDrillSizesChart.pdf

Standard NPT Tap Drill Sizes
NPT Size	Tap Drill Size (in.)	Decimal Equivalent (in.)
1/16 – 27	“C”	0.242
1/8 – 27	“Q”	0.332
1/4 – 18	7/16	0.438
3/8 – 18	9/16	0.562
1/2 – 14	45/64	0.703
3/4 – 14	29/32	0.906
1.0 – 11 – 1/2	1-9/64	1.141
1 – 1/4 – 11 – 1/2	1-31/64	1.484
1 – 1/2 – 11 – 1/2	1-23/32	1.719
2.0 – 11 – 1/2	2-3/16	2.188
2 – 1/2 – 8	2-39/64	2.609
3.0 – 8	3-15/64	3.234

1 Response to "Standard NPT Tap Drill Sizes Chart"

Machinist Family

July 9, 2014 at 10:35 pm

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